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Center Wheel Play- how much is too much?


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Hello All,

I'm looking for a little insight from experience.  I've got a Valjoux 71 movement that I'm working on which has poor amplitude.  The mainspring looks fine (although a replacement will be in shortly) and I haven't found issues with he pivots or jewels yet.  The drum seems okay in it's bushings too.  The center wheel has quite a bit of play in my opinion though.  I've attached a vid from under the microscope as evidence.  Anyone with more knowledge on the subject (or experience) please chime in!   For the rest of us newbies, we can just take a vote- too much side shake?  Yes or No?

Thanks!

M20170616_006.mp4

Edited by RyMoeller
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Thanks for the input @clockboy, I thought it was pretty bad but appreciate the confirmation.

There is no center jewel for this movement.  I'll pull the center wheel and take a look at it though.  I'll see if I can get some good pictures of the hole too.

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I think I see a repair by Mark where he fitted a jewel to support the centre wheel.

That will be helpful as it looks like I may have to go that route too.

Interestingly the hold doesn't really look worn- as you can see from the image attached the silver plating hasn't even worn off yet.

IMG_3021.thumb.JPG.14250f73e8b193b188e76f5d7cd6890c.JPG

The center wheel looks okay too.  Strange how the fit is so poor. 

IMG_3023.thumb.JPG.704d8d470de3dc04d4dc3998c85217d5.JPG

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Is it the original center wheel, or was it replaced by someone with something that was close to fitting?

That did occur to me.  I've spent the afternoon trying to track down an affordable replacement as opposed to modifying the plate (by adding a jewel or bushing).  There are a couple of other issues that suggest a less than stellar repair (one of the chronograph eccentrics has been glued into the top plate).

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Hi Ry,

Cousins has a centre wheel but it's £26.

I can't play your video on an iPad, so can't comment on the fit.

S

No luck with Cousins I'm afraid.  They've got the chronograph runner (8000) but not the large center wheel (206).  I've got a few other places to check but thus far the only option is pretty expensive- $74 USD!

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I have just looked at the video and that is bad. If you decide to fit a jewel or a brass bush be careful when you to pushing the cannon pinion back on, you could push the jewel or bush out. The hole in the plate has some nasty scoring which looks as if at some point a hard piece of dirt has been stuck in the hole and has been rotating. The steel that the wheel has been made of is much harder then the bottom plate.

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No luck with Cousins I'm afraid.  They've got the chronograph runner (8000) but not the large center wheel (206).  I've got a few other places to check but thus far the only option is pretty expensive- $74 USD!

D'oh, sorry, brain not engaged.

Jules Borel lists a Valjoux 71 and a 71GHH; they list a stock number for part 206 against the GHH and a price of $14.30, but the stock code comes back as "no items found". Not sure what this means as I normally encounter in stock or out of stock. May be worth calling them.

At $72, it sounds like a brass bush would be a good option. I would be inclined to solder it in place to prevent the problem Oldhippy describes

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I have just looked at the video and that is bad. If you decide to fit a jewel or a brass bush be careful when you to pushing the cannon pinion back on, you could push the jewel or bush out. The hole in the plate has some nasty scoring which looks as if at some point a hard piece of dirt has been stuck in the hole and has been rotating. The steel that the wheel has been made of is much harder then the bottom plate.

 

Ah thanks for the tip regarding the cannon pinion and a replacement jewel.  That's a headache I'd sure like to avoid!

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D'oh, sorry, brain not engaged.

Jules Borel lists a Valjoux 71 and a 71GHH; they list a stock number for part 206 against the GHH and a price of $14.30, but the stock code comes back as "no items found". Not sure what this means as I normally encounter in stock or out of stock. May be worth calling them.

At $72, it sounds like a brass bush would be a good option. I would be inclined to solder it in place to prevent the problem Oldhippy describes

I agree, it looks like a jewel or bushing is the way to go at this point.

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